Telegraph printing, recording, and like apparatus



1939. I F. WARBURTON I 2,143,002

TELEGRAPH PRINTING, REGORDI NG, AND LIKE APPARATUS Filed Sept. 50, 1956 9 Sheets-Sheet l 4 Fred Warbaarpiorc,

Feb. 21, 1939. F. WARBURTON 2,148,002

TELEGRAPH PRINTING, RECORDING, AND LIKE APPARATUS Filed Sept. 50, 1956 9 Sheets-Sheet 2 In wade? J9 lw'ed Warbwnon, a 74944. 0?. 4%?

Feb. 21, 1939. WARBURTQN 2,148,002

TELEGRAPH PRINTING, RECORDING, AND LIKE APPARATUS Filed Sept. 50, 1956 9 Sheets-Sheet 3 R j'nJ erci'or 'red Warbwrflon,

om fiioriz qy Feb. 21, 1939. F. WARBURTON TELEGRAPH PRINTING, RECORDING, AND LIKE APPARATUS Filed Sept. 30, 1956 9 Sheets-Sheet 4- RM WEE- flu c7180 Fred, Warmr t'olb,

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9 Sheets-Sheet 5 Feb. 21 1939. F. WAR-BURTON Filed Sept. 30, 1936 TELEGRAPH PRINTING, RECORDING, AND LIKE AEPARATUS 1 F d warocrfowz.

Feb. 21, 1939. F. WARBURTON TELEGRAPH PRINTING, RECORDING AND LIKE APPARATUS Filed Sept. 50, 1936 9 Sheets$heet 6 1 int cantor Fred Warbar ton,

Feb. 21, 19 39. F. WARBU'RTON 2,148,002

TELEGRAPH PRINTING, RECORDING, AND LIKE APPARATUS Filed' sept. 30, 1956 9 Sheets-Sheet Fred h zrburion,

Feb. 21, 1939. F. WARB RTON 2,148,002

TELEGRIWH PRINTING, RECORDING. AND LIKE APPARATUS Filed Sept. 30, 1936 9 Sheets-Shet a v #1; \Q Q M Feb. 21, 1939 F. WARBURTON 2,148,002

TELEGRAPH PRINTING, RECORDING, AND LIKE APPARATUS Filed Sept. 50, 1956 9 Sheets-Sheet 9 WMQM Patented Feb. 21, 1939 PATENT OFFICE TELEGRAPH PRINTING, RECORDING, AND LIKE APPARATUS Fred Warburton, London, England, assignor to Cable and Wireless limited, London, England, a

British company Application September 30, 1936, Serial No. 103,437

'In Great Britain October 8, 1935 38 Claims.

This invention relates to telegraph apparatus and is particularly concerned with .apparatus which is arranged to deal with signals in unequal length codes, such as cable Morse code, in which the various signals are composed of different numbers of units. The invention, however, is also applicable to apparatus which deals with equal length codes such as five-, sixor more unit codes. Further, apparatus embodying the invention may be arranged to operate on the start-stop principle or itmay be arranged to deal with code transmitted and received on continuously-driven mechanism.

An object of the invention is to provide mechanism for setting up permutations for use in telegraph printing or perforating mechanism, the permutations consisting of the setting of the positions of a number of permutation members such as combs. Thus, one of the principal features of the invention consists of permutation setting mechanism comprising an actuator which is rcciprocated constantly and which is arranged under the control of a signal to be brought into operative relationship with a number of interposed members in succession. This result may be eifected by a kind'of unlatching of the members in succession of freeing them to come into the operative path of the actuator so long as si nal impulses are applied to the apparatus. In the case of a variable length code, such as cable Morse code, each interposed member, after performing its function, relatohes itself and unlatches the next of the series of interposed members for it, in its turn, to be allowed to come under the sphere of influence of the actuator. The mechanism is arranged so that when a condition exists corresponding to the sending or reception of spheres in telegraphy, the successive unlatching and latching of the difi'erent interposed members is interfered with and is not allowed to proceed and also when the spacing conditions follows on the completion of the impulse or impulses forming a character, all the interposed members are reset and the initial or zero state of affairs is produced once more ready for the next signal.

A further object of the invention is to provide a translating mechanism which enables permutations set up on permutation members, such as combs, in.'telegraph printing apparatus or like such as the cable Morse code or Wheatstone Morse code. In the case of equal length codes such as five-unit, six-unit code, and so forth, the permutations set up can be dealt with and translated at equal intervals because each char- 5 acter is constituted by the same number of impulses. The matter, however, is not so simple in the case of unequal length codes because the characters consist of unequal numbers of signal elements. The invention, therefore, provides con- 1 stantly-driven exploring members, which, for example, may conveniently take the form of pivoted blades, which are arranged to coact with the permutation combs or other permuation members at the end of every centre-hole unit. Thus, the permutation combs are set at the end of each signal in the usual manner to allow the entrance or passage of a single one of these exploring members which control the actuation of the type bars and so forth. However, if the permutation members are thus explored once per centre-hole period in this way, it is clear that, without further provision, a character would be printed inevitably after the first impulse of each signal, the character being an e if the impulse is a dot and a t if it is a'dash. To obviate this difllculty, a space comb or other permutation member is provided which prevents the printing operation until, when upon'the completion of a character signal, this space comb has been displaced to act as a gate for the appropriate exploring member.

The invention is also concerned with printing, typewriting, recording and like mechanism, arranged to be operated under the control of 5 permutation settings, and according to a further aspect of the invention, printing, typewriting or like mechanism is controlled from a series of constantly actuated exploring members which co operate with a series of permutation members 40 such as combs, the exploring members being associated with a mechanism arranged to select the appropriate type members to be power-driven from a separate source of power such as an electric motor.

The series of exploring members may be pivoted about a common spindle and arranged so that each one which is not selected is caused to execute one species of motion, while the member that is selected undergoes another species of motion. Thus when the exploring members cooperate with the permutation members, those exploring members that are not selected may be caused to rock as a result of contact with the permutation members while the selected exploring member enters a gate or the like formed as a result of the permutation members being set so as to bring slots in the permutation members into alignment.

Further objects and aspects of the invention will appear from the following description.

In order that the invention may be clearly understood and readily carried into effect, telegraph receiving apparatus constructed in accordance therewith will now be described, by way of example, with reference to the accompanying drawings in which:

Figure 1 is a front elevation of the apparatus;

Figure 2 is a circuit diagram showing certain circuits including three electromagnets, seen in Figure 1;

Figure 3 is a perspective view of certain selector and permutation setting mechanism contained in the apparatus;

Figure 4 is a perspective view of certain details of the mechanism shown in Figure 3;

Figure 5 is a view similar to Figure 4 but showing a somewhat different selection of details;

Figure 6 is an exploded perspective view of some parts seen in Figures 3, 4 and 5;

Figure 7 is a somewhat diagrammatic sectional elevation of type selecting and actuating mechanism contained in the apparatus;

Figure 8 is a perspective view of certain details of the mechanism shown in Figure 7;

Figure 9 is a perspective view of letter spacing mechanism incorporated in the apparatus;

Figure 10 is a perspective view of paper feed mechanism incorporated in the apparatus;

Figure 11 is a perspective view of word spacing mechanism incorporated in the apparatus;

Figure 12 is a perspective view of a call device, together'with some associated mechanism, incorporated in the apparatus;

Figure 13 is a diagrammatic elevation of certain parts shown in Figure 7 and of associated parts not shown in that figure;

Figure 14 is a perspective view of further mechanism incorporated in the apparatus; and

Figure 15 is a diagram showing the arrangement of driving mechanism for the apparatus.

The apparatus illustrated may be controlled by perforated tape fed through a distant transmitter,

length code, such as fiveor six-unit code. Never- -theless, in the following description the operation of the apparatus will be described on the assumption that the signals received are derived from tapie perforated in accordance with cable Morse C0 P.

Referring first to the selector and permutation setting mechanism (see Figures 1 to 6), this includes three electromagnets (Figures 1 and 2) consisting of a magnet I which is energised upon receipt of an impulse representing a dot, a magnet 2 which is energised upon receipt of an impulse representing a dash and a space magnet 2 which is energised whenever a marking impulse i. e., a dot impulse or a dash impulse is received. The magnets I, 2 and 3 are controlled through the medium of a tongue l (Figure 2) of a receiving relay RR. The tongue l rests in a central or neutral position when a spacing condition obtains but is swung to right or left when a marking impulse passes along the line 5. The direction of the current impulse in the line 5 determines in which direction the tongue l is moved and consequently whether the dot magnet I or the dash magnet 2 is energised. In both cases the space magnet 3 is energised. This space magnet 3, upon being energised, attracts an armature 6 (Figures 1, 3 and 5) and swings it, against the action of a spring 6a, about a horizontal axis at its lower end at which it is anchored by a resilient leaf. The armature 6 controls the movement of an actuator I which consists of two levers connected together by a transverse bar Ia. This actuator 'I is pivoted about the axis of a horizontal spindle lb to a frame 8 arranged to be rocked about the axis of a horizontal spindle 8a. This frame 8 is rocked up and down once for each centre-hole interval of the tape from which the signals are received. The mechanism for rocking the frame 8 is shown in Figure 11 and includes a shaft 8l, carrying an eccentric I0, which is rotated at a speed such that it makes one revolution during the time interval between the arrival of two consecutive centre holes at the exploring device associated with the tape. The eccentric III lies in a corresponding bearing at one end of a connecting link II pivoted at its other end to a frame l2, pivoted about the axis of a horizontal spindle l2b. The latter is formed with an arm I211 which is connected to the frame 8 through the medium of a .universal joint including a member I3 pivoted respectively to the frame I2 and to the frame 8 about axes at right angles.

Now supposing a spacing condition obtains so that the armature 8 is not attracted by the space magnet 3, then the upper end of the armature 6 lies in the path of two projections 10 on the actuator I so that when the latter is carried downwards by the rocking frame 8, the engagement of the armature 6 with the projections 10 causes the actuator I to be swung about its axis 1b in an anti-clockwise direction as seen .in Figures 3 and 5. The result of this is that during its downward movement, the actuator 1 has no effect on the permutation setting mechanism except that during its first downward movement after a marking condition it swings a latching lever Ila about the axis of a spindle I5 due to the engagement of the transverse bar Ia of the actuator with an inclined edge on a projection I8 forming part of the latching lever Ila. This downward movement of the latching lever Ila causes a shoulder I'l, formed on the latching lever Ila, to be moved out of engagement with a lug I 811 formed on an interposed member I la. The result of this is that the interposed member Ila is swung in an anti-clockwise direction (Figure 3) by a wire spring flawhich bears against a toe 2| formed at the lower end of the interposed member Ila. The interposed member Ila is one of seven such interposed members I84 I. These interposed members are pivoted respectively to seven rocking plates 22a 220 and the rocking plates are pivoted about a common horizontal spindle 23. The spring 2l is bent round the spindle 23 and is prevented from moving bodily in a clockwise direction (Figure 3) by a cross bar 2l. Wire springs 2lb 20g, associated respectively with the interposed members Ilb I99, are arranged in a similar fashion.

During a spacing condition the actuator I is simply raised and lowered by the frame 8 and after having caused the latching lever Ila to unlatch the interposed member ISa'it has no further action on the interposed members until a markin impulse is received. At the top of its stroke, the transverse bar Ia of the actuator is in contact with a downwardly extending projection 28 formed on a fixed bracket 26, but as soon as the projections 10 encounter the top of the armature 6 near the beginning of the downward stroke of the actuator I, the latter is swung against the action of a spring 21, about the axis of the spindle 11) so that the transverse bar Ia is not only moved away from the projection 25 but also clears all the interposed members including the unlatched one I9a, and moves downwards and then upwards without touching these. However, as soon as a marking impulse is received, the space magnet 3 attracts the armature 6 against the action of the tension spring 6a so that the armature does not coact with the projections Ic on the actuator I. The result of this is that the actuator I is lowered and raised in a different path, due to the fact that the spring 21 is permitted to hold the transverse bar Ia continuously against the fixed projection 25. The armature 6 of the space magnet is locked in its unattracted position (by means described below) during the major portion of each complete oscillation of the actuator I while a spacing condition obtains, but is unlocked each time the actuator I reaches its uppermost position. Thus when a marking condition arises, the armature 6 is permitted to swing towards the space magnet 3 the next time the actuator I approaches the top of its stroke. Then, during its next downward stroke the transverse bar Ia of the actuator I bears on a shoulder 28a formed on the interposed member I9a which, having been unlaiched and moved forward by the spring 200., lies in the marking path of the transverse bar Ia. Thus the associated rocking plate 22a is swung about the spindle 23 as the actuator I presses the interposed member I9a downwards. During its downward movement a lug 29a, formed on the interposed member Illa bears on one end of a latch member I4b associated with the next interposed member I912. The result of this is that the interposed member l9b is unlatched and swung by its associated spring 20b in an anti-clockwise direction (Figures 3 to 5) so that it is ready to be moved. downwards by the actuator I during the next downward stroke of the latter, provided that a spacing condition does not arise before this stroke takes place. There are, in fact, five further latching levers I40 Hg associated respectively with the interposed members 19c I99. The latching levers I4b My are very similar to the latching lever I la except that none of them is provided with an extension I6 for co-operation with the transverse bar Ia of the actuator I.

' From the foregoing it will be seen, generally, that the arrangement is that when one of the interposed members l9a I9 is pushed downwards by the actuator I, the next interposed member l9b I99 is automatically released by its associated latching lever Mb Mg so that it takes up a position ready to be depressed by the actuator I during the next downward stroke of the latter. Returning to the interposed member [9a, when this is pushed downwards a bevelled edge 3Ia formed thereon snaps past a bevelled edge formed on a cross bar 32, fixed to a re-latching frame 33, arranged to rock about the axis of a horizontal spindle 34. The frame 33 is loaded by a spring 35 so that the frame 33 always tends to swing in an anti-clockwise direction (Figures 3 and 4) and bears against the back edges of the on the frame 33, so that the interposed member l9a is caused to swing about the pivot by which it is connected to the rocking plate 22a while the edge 36a turns on the cross bar 32 which acts as a fulcrum, the interposed member being thus swung back to its initial position. As soon as the interposed member IBa reaches this. position the latching lever Ma engages the lug Im on the interposed member I90. and holds the latter until the transverse bar Ia of the actuator I again engages the projection IS on the latching lever Ma at the beginning of the next spacing condition. Seven wire springs 30 (similar to the wire springs 20a 209), one for each of the latching levers I la Mg, are arranged to hold the latching levers in their latching positions.

It will be seen that the interposed members, starting with the interposed member I So, are unlatched, actuated, and then latched again in succession. However, as previously indicated, the operations of the interposed members overlap because, with the exception of the first interposed member l9a, each one is unlatched as a direct result of the actuation of the previous one that was unlatched. In the case of cable code, not all the interposed members l9a 99 are unlatched for each signal but the number of interposed members unlatched for each signal is the same-as the number of impulsesin that signal. Thus, if the signal received is a single impulse signal, that is e or if, only the first interposed member Illa will be actuated, but usually, of course, the signal received will result in more than one member being actuated, i. e., being depressed by the actuator I. As explained above, when any interposed member 19a Hg is actuated, this results in the next interposed member being unlatched so that, usually, after the appropriate number of interposed members have been actuated in-accordance with a received signal, there will be one interposed member which is unlatched but which is not depressed by the actuator I so that it cannot be returned to its initial position as a result of the engagement of its edge 36 with the cross bar 32 on the relatching frame 33. After the last interposed member, assuming this not to be the member l9g, has been actuated during the last impulse of a received signal, the transverse bar Ia of the actuator I will follow its forward or spacing path during its next downward movement on account of the engagement of the projections 10 with the armature 6, the latter having been released immediately upon the start of the first spacing interval following the last marking interval of the signal. The forward movement of the actuator I due to the engagement of the projections Ic with the armature 6 results in one edge of one of the vertical parts of the actuator I pushing on a roller 49a carried by the lower end of a lever 49, pivoted about a horizontal axis at its centre. When this happens the upper end of the lever 49 pushes on a lug 50a formed on a plate 50, pivoted about the axis of a horizontal spindle 50c carried by the fixed bracket 26. The plate 50 is thus caused to swing about its axis and bear upon the remaining unlatched interposed member I9b 199 so as to move the latter back to the position in which it is engaged and held by its associated latching lever (Mb Hg). The plate 50 hangs down behind the fixed bracket 25 and is bent forwards and downwards at 50!) so that it extends down wards in front of those parts of the interposed members that are above their shoulders 28.

When marking conditions obtain the path of the actuator 1 is such that it does not cause the lever 49 to act on the plate 58. I

The interposed members |9a I 90, of course, are all the same shape except that the last interposed member |9g is not provided with a lug 29a 29] because there is no further interposed member to be unlatched upon actuation of the member I90.

Each of the rocking plates 22a 22! is pivoted at its end remote from its associated interposed member to a pair of L-shaped levers 91a 11], 98a 98!, while the rocking plate 220 has a single L-shaped lever 58:: pivoted to its end. .The end of each rocking plate 22a 22g is formed with a circular part 19 which fits into a corresponding circular recess in the associated one of the L-shaped levers 31a 91! and 98m. The end of each rocking plate 22a 22f also carries a disc 44 which fits into a corresponding hole in the associated one of the L-shaped levers 38a 98f. The horizontal arms of the L.- shaped levers 31a 910, 88a "a and 38:: are formed so as to co-operate with frames 4| and 42 pivoted together about the axis of a spindle 43. An armature 45 for the dot magnet I is fixed to the frame 4|, while the frame 42 carries the armature 48 associated with the dash magnet 2. The amount of movement of the armatures 45 and 48 is limited by stops 45a and 45a (Figure 1). Incidentally, also, the movement of the space magnet armature 8 is limited by the ends of a slot in a fixed member 81). The arrangement of the frames 4| and 42 is such that if the magnet l is energized when one of the rocking plates 22a 22! is turned about the axis of the spindle 23, a cross piece 41, forming part of the frame 4|, is engaged by one of the L-shaped levers 31a 31] associated with this particular rocking plate so that this L-shaped lever is turned about the axis of the circular part 99 formed on the rocking plate. The associated one of the L-shaped levers 98a 881, however, is not engaged by the frame 4| and is simply raised bodily by the associated rocking plate without being turned. On the other hand, in the event 'of the armature 48 being attracted by the dash magnet 2 when one of the rocking plates 22a 22] is turned, the associated one of the L-shaped levers 38a 38! is turned about its axis by a cross piece 48 on the frame 42, while the associated one of the levers 91a 81! is not turned. The L-shaped levers 81a 91a, 88a 58g and 382: are held against turning in a clockwise direction, as seen in Figure 3, -beyond the positions which they take up when they are idle, by a fixed bar 5|. bar 52 limits the upward movement of those ends of the rock-plates 22a 220 that carry the interposed members |9a I90. The cross pieces 41 and of the armature frames 4| and 42 are located so that if the L-shaped levers 81a 31] and 98a II! were raised when neither the dot magnet I nor the dash magnet 2 was energized, the cross pieces 41 and 48 would enter gaps between ends of the L-shaped levers 91a 31f and shoulders 540 on the L-shaped levers 38a 88] so that these L-shaped levers would not be turned about their axes. Further. the L-shaped lever 98:: is formed so that, if the rocking plate 220 was rocked so as to raise the L-shaped lever 34:: when neither the dot magnet I nor the dash magnet 2 was energized, the cross pieces 41 and 48 would enter a notch (Figure 6) between shoulders 54a and 540, in the L-shaped Further a fixed lever 38:: so that this also would not be turned about its axis. When the armature 48 is attracted, the cross piece 48 on its frame 42 engages the top of a part 54 of the one of the L-shaped levers 98a 98f that is raised as a result of the actuator 1 being caused to act on the associated one of the interposed members. The associated L-shaped lever 31a 31! is unaffected because, in this case, the cross pieces 41 and 48 of the frames 4| and 42 both he beyond the ends 58 of the L-shaped levers 31. When the armature 45 is attracted by the magnet l the cross piece 41 of the frame 4| lies above the horizontal part of the one of the L-shaped levers 91a 31f that is raised, so that this lever is turned about its axis. The associated L-shaped lever 98a 38 is not turned, in this case, because both the cross pieces 41 and 48 lie above gaps in edges of the L-shaped levers 38a 989. In the case of each L-shaped lever 98a 98! this gap extends between its shoulder 54:: and a shoulder 54b. When a spacing condition obtains the frames 4| and 42 are held in their central or neutral position by a spring 55. A stop 55a prevents one frame from moving when the other frame is moved by its associated magnet. The gap between the shoulders 54a and 540 in the L-shaped lever 38:): is shorter than the gaps in the L-shaped levers 94a 38 and is such that, if the armature 45 is attracted, when the L- shaped lever 38a: is raised, the lever is turned about its axis due to the cross piece 41 of the frame 4| engaging a part of the L-shaped lever 38:: on one side of the gap, while if, on the other hand, the armature 46 is attracted, the cross piece 48 engages the part 54 on the other side of the gap. Thus, whenever the rocking plate 22g is rocked as a result of the actuator 1 acting on the interposed member I99, the consequent raising of the L-shaped lever 38:: results in this being turned about its axis, whether the impulse received represents a dot or a dash. The L-shaped lever 38:: serves a particular function described below.

The L-shaped levers 81a 81f, 38a 38! are arranged to act respectively on twelve permutation combs 58, upon the arrangement of which depends the particular character that is to be printed, while the L-shaped lever 38:1: is arranged to act on an additional comb L However, before dealing with these combs it may be mentioned that means are provided for locking the armature of the magnets and 2 in position during each centre-hole interval. Thus, an eighth rocking plate 51 is mounted on the spindle 29. This rocking plate is similar to the rocking plate 22a 22g and carries L-slnped levers 58 and 59 at its end. These L-shaped levers 58 and' 59 are mounted on the rocking plate 51 in the same way as the L-shaped levers 21a 31 and 38a plates 22a 221', but the levers are not associated with any combs and the ends of their horizontal parts are formed somewhat differently from the ends of the horizontal parts of the L-shaped levers 81a 811 and 38a 38f. Thus, the end of the lever 58 is formed with a small vertical lug 58, while the end of the lever 59 is formed with a small vertical lug 6|. These lugs 88 and 6| are so disposed that if the L-shaped levers 58 and 59 are raised by the rocking plate 51 when the magnets and 2 are not energized, that is to say, when the frames 4| and 42 are in their neutral positions, the lugs 60 and 8| are moved into positions such that they lie 881 are mounted on the rocking one on each side of the two cross pieces 41 and 88 of the armature frames 4| and 42. If, however, the dot magnet I is energized when the L-shaped levers 58 and 59 are raised, the cross piece 41 of the armature frame ll moves to the side of the lug 8ll remote from the lug 8| so that the lug 88 is raised to a position between the cross pieces I and 48 of the armature frames II and 82 and holds he armature frame ll in the position which it takes up upon energization of the magnet I, until the L-shaped levers 58 and 59 are lowered. In the event of the dash magnet 2 being energized, the cross piece 48 of the armature .l'rame 42 is moved to the side of the lug 8| remote from the lug 89, so that when the L-shaped levers 58 and 59 are raised, the lug 8| moves to a position between the cross pieces 41 and 48 of the armature frames ll and 82 and holds the armature frame 42 in the position which it takes up when the dot magnet I is energized until the plates 58 and 59 are lowered. Hairpin springs 82 and 83 engage small V-shaped notches formed respectively in lugs on the lower edges of the L -shaped levers 58 and 59. These hairpin springs 82 and 83 control the paths in which the lugs and 8| move, maintaining these paths constant at all times when the apparatus is working normally, but permitting the L-shaped levers 58 and 59 to yield in the event of any abnormal contact between the lugs 88, 8| and the cross pieces 41 and 88 of the armature frames ll and 42. The L-shaped levers 58 and 59 are raised and lowered each time the actuator I is lowered and raised. Thus, the rocking plate 51 has a member 84 pivoted to its end remote from the L-shaped levers 58 and 59. The member 84 is formed on its upper end with two lateral lugs 85 which lie one on each side of the vertical parts of the actuator 'I. when this vertical part of the actuator I is lowered, a lug 88, formed thereon, presses on one of the lugs 85 and moves the member 84 downwards so that the L-shaped levers 58 and 59 are raised. The return movement of the rocking plate 51 is positively insured by the engagement of the spindle lb with a heel 253' formed on the plate 51, during the upward movement of the actuator I. The rocking plates 22a 22g are formed with similar heels for the same purpose.

when a spacing condition obtains at the beginning of a centre-hole interval and the space magnet 3 becomes energized during this interval, the armature 8 of the space magnet 3 is (aspreviously indicated) positively held against movement until the end of the interval. This is because a lever 88, having a downwardly projecting lug 89 on one end is caused to swing downwards with the reciprocating frame 8 so that the lug 89 engages the armature 8 and holds it against being attracted by the magnet 3 until the reciprocating frame 8 has been raised sufliciently to allow the lug 89 to clear the armature 8. The lever 88 is pivoted to the frame 8 about the axis of the spindle lb so that when the frame 8 is swung downwards again the upper edge of the armature 8, which now lies in the path of the lug 89 on the lever 88, engages the end of the lug 89 and. causes the lever 88 to swing about the axis of the spindle lb relatively to the frame 8 against the action of a spring IIIL It will be seen, therefore, that the lever 88 locks the armacurs. The armature 8 is, in fact, locked in its attracted position by the ends of the projections Ic on the actuator I which, during much of each marking oscillation of the actuator I, engages one face of the upper end of the armature 8.

Returning to the permutation combs 58, these are arranged to be thrust longitudinally against the action of wire springs II by the L-shaped levers 31a 31] and 38a. 38 and each comb is formed with a number of notches in its upper edge. It will be seen that for each signal received a selection of the combs is moved longitudinally to the left, as seen in Figures 3 to 5, according to which of the L-shaped levers 31o 31; and 38a 38f are rocked about their axes, the setting of the combs depending upon the signal received. In extreme cases the signal may result in only one of the permutation combs being moved or in six permuation combs being moved. During spacing intervals none of the permutation combs are moved. The apparatus is, as will be appreciated from the fact that there are twelve permutation combs, only capable of dealing with signals which consist of not more than six impulses. The thirteenth comb 25l is not actuated during normal signalling and its purpose will be described below. There is, however, a fourteenth comb which is a space comb I4 that is moved automatically each time after the permutation combs 56 are set in accordance with a received signal. For each signal that necessitates the printing of a character, the notches in the combs take up relative positions such that one of a number of exploring blades I2, which are brought to bear periodically on the upper edges of the combs can enter a number of notches, one in each comb, which happen to be in register. Each exploring blade I2 can only enter the notches associated with the exploring blade when the notches are in register, that is to say, only when the signal corresponding to the respective exploring blade I2 is received.

As soon as a comb 58 is moved to the left, as seen in Figures 8 to 5, by its associated one of the L-shaped levers 31a 311 or 38a. 38 it is locked in the position to which it is moved by a latching lever I3 which drops into a latching notch 13a, as many latching levers I3 as there are combs 58 being provided. Thus, although when a permutation comb has been moved longitudinaliy by its associated one of the L-shaped levers 31a 31; or 38a 38f, this lever is immediately lowered so that it no longer engages the comb, the latter does not thereupon return to its initial position but is held against such return movement by its associated latching lever l3. When a complete signal has been received and the permutation combs 58 have been set in accordance with that signal, the exploring blade I2 associated with the signal cannot immediately enter the corresponding notches in the combs 58. The reason for this is that the exploring blades I2 can never enter slots in the combs 58 until the space comb I4 has been moved to the left as a result of the space condition which immediately follows each complete signal received. The exploring blades are brought to bear on the upper edges of the combs once every centre-hole interval. This is necessary because the signal-received may consist of a single impulse only, as for example when the signal represents e or t. In the absence of the space comb 14, therefore, an exploring blade I2 would enter notches in the permutation combs after only one of these had been moved and before other combs corresponding to the signal being received had had time to be moved. The character e or the character t would then be printed when, in fact, the signal received corresponded to another character consisting of more than one impulse. The provision of the space comb 14, however, makes certain that no exploring blade can enter slots in the permutation combs until the character received has been completely set upon the permutation combs 56 and a spacing condition has supervened. The space comb I4 is formed with notches in its upper edge corresponding to every exploring blade, and it is not until the space comb I4 has been moved to the left and brought its notch corresponding to the signal received into register with the alined notches in all the combs 56 and so has completely opened a gate, that there is freedom for the corresponding exploring blades to enter the alined notches. It must be borne in mind that the additional comb MI is never moved during normal signalling and is provided with notches which permit any exploring blade that happens to be selected to enter notches in the other combs when these are appropriately set. While signal impulses are being received the space comb I4 is held to the right as seen in Figure 3 by one of the wire springs II. As soon, however, as the ensuing spacing condition intervenes after the signal impulses have all been received, the return of the armature 6 to its unattracted position results, as explained above, in the actuator I being raised and lowered in a somewhat different path and in the transverse bar Ia of the actuator I being moved to the left (as seen in Figure 3) on account of the engagement of the projections 10 on the actuator I with the armature 6 of the space magnet 3. This movement to the left of the transverse bar la of the actuator 1 causes an interposed member 16 to be pushed to the left and the end of the interposed member I6 remote from the transverse bar Ia pushing the space comb I4 to the left. The interposed member I6 is connected to one end of an arm 11 which is pivoted about the axis of a spindle 18. The space comb I4 is latched in the position to which it is moved by a latch member 13 similar to the latch members 13 associated with the permutation combs 56.

The exploring blades 12 are carried by a spindle 19 mounted on levers 80 pivoted on journals 80a.

The levers 80 are plvotally connected at their ends remote from the spindle '19 to eccentric rods 8| having bushes 82 at their lower ends which embrace eccentrics 83 mounted on a continuously rotated shaft 84. The shaft 84 is rotated at such a speed that the eccentrics 83 cause the exploring blades I2 to be brought, as indicated above, into contact with the combs 56, 25I and 14 at the end of each centre hole interval.

An eccentric 85 is also fixed to the shaft 84. This eccentric 85 is embraced by a bush at one end of an eccentric rod 86, the other end of which is pivoted to a bell crank lever 81 which can swing on a journal 08. Thus, an upstanding lug 89 at one end of the bell crank lever 81 is caused to oscillate up and down by the eccentric 85. The majority of the oscillations of the bell crank lever 81 are idle, but the movement to the left of the space comb I4 causes a shoulder 80 on the space comb 14 to push a frame 9| to a position such that a transverse portion thereof lies in the path of the lug 89. The frame 9| is pivoted about the axis of a horizontal spindle 92 to a frame 9Ia pivoted about the axis of a horizontal spindle 9Ic. Thus, when the shoulder 90 of the space comb I4 is caused to push on the frame 9|, the latter is able to move because the frame 9Ia yields, against the action of a tension spring 9Ib, about the axis Me. The eccentrics 83 and 85 are arranged relatively to each other in such a Way that soon after the space comb has been shifted the exploring blades 12 are brought into contact with the combs so that the selected exploring blade can enter the corresponding slots in the combs. Then, immediately following the removal of the exploring blades 12 from contact with the combs the cocentric 85 brings thelug 89 on the bell crank lever 81 into contact with the frame 9|. The lug 89 then swings the frame 9| upwards, about the axis of the spindle 92, against the action of a spring 93. The frame 9| extends under the latch members I3 so that when it is raised, it lifts the latch members that are latching their associated combs. Thus, those combs that have been latched are returned by their wire springs II to the positions from which they were originally shifted. The latch members I3 are held in their latching positions by springs 13b which force the latch members 13 into engagement with the corresponding notches in the combs. Each exploring blade 12 is held by a spring I00, connected between an upstanding part I 0| of the exploring blade and a fixed point, so that the part IOI rests against a rest 99 (common to all the exploring blades) during that part of the movement of the exploring blades that takes place before and after they engage the combs. When the exploring blades 12 engage the combs, all the blades, with the exception of any blade that can enter alined notches inthe combs, are swung about the axis of the spindle 18, against the actions of their springs I00, because the blades 12 swing about the space comb I4 during continued downward movement of the spindle 19. This movement of the blades I2 results in lateral lugs I02, at the upper ends of their upstanding parts IOI, traversing paths such that they do not engage lugs at the ends of arms I04a of three-armed levers I04 (Figure 7). There is one of these three-armed levers I04 associated with each exploring blade I2 and all the threearmed levers I04 are mounted to swing on a common horizontal spindle I05.

When an exploring blade 12 enters notches in the combs, its lug I02 traverses a path such that it engages the lug at the end of the arm I 04a of the associated three-armed lever I04 and swings the latter about the spindle I05. The three-armed levers I04 are associated respectively with a number of hook members I06. Each hook member I06 is connected to an arm I041) of its associated three-armed lever I04 by a spring I01. When a three-armed lever I04 is turned as .a result of the selection of its associated exploring blade I2 a hook 1411 on an arm I040 of the three-armed member I04 engages the associated hook member I06 so that the two hooks are held latched together by their associated spring I01 even after the exploring blade has been removed from the combs. The lower arms I040 of the three-armed levers I04 carry blade springs I08, the lower extremities of which enter slots in associated slides I09. Thus, when a three-armed lever I 04 is selected and turned, its blade spring I08 tends to move the associated slide I09 from left to right as seen in Figure 7. This movement may take place immediately the three-armed lever I 04 is actuated but in some phases of the actuation of the mechanism the nose IIO of a type actuating lever III lies in the way of the right hand end of the corresponding slide I09 and 'holds up the movement of the slide for a short time. There are as many type actuating levers III as there are slides I09 and the type actuating levers III are mounted on a common spindle H2, carried by arms H3 pivoted about the axis of a spindle H4. The arms H3 are caused to rise and fall continuously through the medium of an eccentric link H5, one end of which embraces an eccentric H6 which is rotated continuously by a shaft II'I during the operation of the apparatus.

If, when the type actuating levers III are carried downwards, the nose H0 of one of them is engaged by the end of the associated slide I09, the slide I09 shoots forward as soon as the nose H0 has been moved down far enough to permit this to happen. Then, when the lever III is carried upwards again its nose H0 encounters the lower edge of the end of the slide I09 which is now in its path. As soon as this happens the lever III is swung about the axis of the spindle H2 so that its end remote from the nose H0 is raised against a spring 96 and a type connecting rod I20 pivoted to the lever III, is pushed upwards to effect printing on a paper strip (mentioned below) by the type character 98a, born by a type lever 98. The type levers 98 are pivoted to a fixed semi-circular bracket 91. Dogs I 2|, fixed respectively to the arms II3.and connected by a transverse strip I22, are raised at the same time as the arms H3.are raised, and as soon as the selected type lever 98 has been actuated, the transverse strip I22 engages the tail of the hooked member I06 which has been latched to its associated three-armed lever I 04 and unlatches these members so. that the threearmed lever I04 is returned by the spring I01 to its normal position and pulls its associated slide I09 to the left (as seen in Figure '7) It may be noted that the mechanism disclosed permits of operation with the shaft I I1 rotated at the same speed as the shaft 84 or at half that speed. In the former case, when the shaft I I1 is geared to the shaft 84 so that both these shafts rotate at the same speed and the spindle H2 is therefore reciprocated at centre-hole speed, the type-actuating levers II I are arranged to be substantially at the bottoms of their strokes each time a selection results in one of the slides I09 being moved forward. Thus, in this condition or phase of the mechanism the nose of no selected slide I09, when it is moved to the right as seen in Figure I, abuts against the nose IIO of the corresponding type-actuating lever III in the manner indicated above. On the contrary, each slide I09 upon selection is moved forward immediately to the position in which its lower edge lies in the path of the nose IIO of the corresponding lever III so as to be encountered by the top of the nose IIO during the upward stroke of the spindle I I2. In the alternative case in which the shaft H1 is geared to the shaft 84 so as to run at half its speed, which is desirable when signals are being received at high speed, as it enables the printing mechanism to work at a reasonably slow speed while the selector mechanism is working fast, it

will be seen that these speeds are possible because,

first revolution resulting in one of the permutation combs 56 being shifted and the second revolution resulting in the space comb I4 being shifted. Thus, the shaft I I! may be run at half the speed of the shaft 84 without any danger of a selected character not being printed. However, it may happen in this phase of the operation of the mechanism that a selected slide I09 may be moved forward when the corresponding type-actuating lever I II is at or near its uppermost position, but it may also happen that the slide I09 is moved forward when the corresponding type-actuating lever III is at or near the bottom of its stroke. The relative positions of these two parts are determined by the number of impulses in the corresponding signal. It is when a slide I09 is moved forward at a time when the corresponding typeactuating lever III is near the top of its stroke that the associated blade spring I08 yields so that the slide I09 is not moved to its operative position until the nose H0 of the associated lever III has been lowered sufliciently for the movement to occur.

The paths which the slides I09 traverse when they are moved longitudinally are controlled by the position of a slot I23a formed in a frame I23 pivoted about the axis of the spindle H4 and loaded by a spring I26. The spring I26 tends to swing the frame about the axis of the spindle I I4 in a direction such that the slot I23a is raised. However, the position of the slot I23a is controlled by a transverse bar I2'I formed with inclined cam edges I2'Ia and I2'Ib that bear respectively on the arms of the frame I23. The position of the slot I23a may thus be adjusted at will by moving the bar I 21 longitudinally.' Each slide I09 is formed at its end remote from the frame I23 with a tongue I09b which projects between two fixed bars I28. This arrangement enables the slides I09 to be moved in vertical planes, when the frame I23 is raised or lowered by moving the bar I2'I, as the tongues I091) turn on the lower bar I 29 which serves as a fulcrum. The adjustment of the frame I23 determines the exact point in the movement of the type actuatinglevers III at which these levers strike their respective slides I09. This adjustment is necessary because, if the apparatus is working at high speed, the printing will be too violent and too deep impressions will be made on the paper strip unless the frame I23 is raised so that the type actuating levers I I I strike their respective slides later in the upward strokes of the type actuating levers II I than is the case when the apparatus is working at a slower rate. The forward movement of the slides I09 to their operative positions is limited by stops I09a which engage the frame I23. I

After a character has been printed, the paper strip has to be fed forward so that a blank part of the strip is brought into position to receive the next character to be printed. Accordingly, mechanism, shown in Figures 9 and 10, is provided for feeding the strip forward automatically.

Actually this mechanism is arranged to be operis swung about its axis so as to move the associated permutation comb 58 longitudinally. This happens whether the signal consists of one impulse or more than one impulse. when the L- shaped levers 31a. and 38a are raised, the-tops of the L-shaped levers push on a bent-over lug I30a at one end of a lever I30 (Figure 9) and swing this lever about ahorizontal axis at its centre so that its end remote from the lug I30a is lowered sufficiently to press a lever I32 downwards to the position shown in Figure 9 against the action of a spring I35 and to enable this spring to swing a bell crank lever I34 to a position in which a shoulder I34a formed thereon locks the lever I30 in the position shown in Figure 9. The lever I32 is pivoted at one end about a spindle I33 carried by the interposed member I8, the lever I32 being turned about this spindle when it is pressed downwards. When at the end of a signal the actuator I moves the interposed member I longitudinally so as to operate the space comb I4, as described above, the lever I32 is also moved longitudinally. This results in a member I36 being turned about the axis of a vertical spindle I38d due to the lever I32 pushing on an arm I3ia of the member I36, this arm' I36a lying in the path of the end of the lever I32 when the latter is depressed by the lever I30 but not when the lever I32 is in its raised position. The movement of the member I36 causes a rod I3I, connected to an arm I380 of the member I36, to be pulled longitudinally so that a stop member I38 is turned against the action of a spring I38a, about the axis of a spindle I39 to a position in which its upper end lies outside the path of a lug I45a (Figure on a pawl I45 mounted on a bell crank lever I40. The latter is rocked to and fro continuously during the operation of the apparatus by means of a connecting rod I42 and a crank pin I43 fixed to a shaft I44. Usually, when the bell crank lever I40 swings in a clockwise direction as seen in Figure 10, the lug I45a engages the upper end of the stop member I 38 so that the pawl I40 is swung against the action of a wire spring I48, about a spindle I4'I which carries the pawl, the spindle I" being mounted on the bell crank lever I40. The result of this is that the pawl I 40 does not engage a ratchet wheel I48. When, however, the stop member I38 is outside the path of the lug I 46a, the pawl I45 is not turned about the spindie I" when the bell crank lever I40 moves in a clockwise direction. Thus, the pawl I45 engages the ratchet wheel I48. The latter is fixed to a paper-feed roller I49, the curved surface of which is serrated and bears against the paper strip. A smooth jockey roller I50 carried by a frame I 5| is caused by a spring I52 to press the strip firmly against the roller I49. Hence, each time the ratchet wheel I48 is turned, the strip is fed forward.

The above described feeding of the strip is, as previously indicated, only sufiicient to provide the necessary space between the two characters in a word and immediately the strip has been fed forward as a result of one operative stroke of the pawl I45, the stop member I38 is returned to the position in which it prevents further feeding of the strip. This return of the stop member I38 is brought about by a projection I32a on the lever I32 (Figure 9) which, after the lever I32 has been moved so as to turn the member I38 a predetermined amount, engages the bell crank lever I34 and swings it so as-to disengage the shoulder I 34a from the lever I30. Thus, the spring I3I is free to return the lever I30 to its initial position. The L-shaped levers 31a and 38a do not prevent the lever I30 from undergoing this return movement because they are lowered just after the lever I30 is latched by the bell crank lever I34 and, incidentally, before the space comb I4 and lever I32 are actuated. When the lever I30 is in its initial or inoperative position, the spring I35 holds the edge of the thick part of the bell crank lever I 34 against one side of the lever I30 and it also holds the lever I32 in such a position that it cannot act longitudinally, if moved, on the member I 38.

Between words it is, of course, necessary to provide longer spaces on the strip than between letters. The illustrated apparatus is constructed so that word spaces may be introduced in either one of two ways. The first way is dependent upon the provision of additional spacing intervalsbetween character permutations on the perforated tape. In this case, therefore, every unperforated centre-hole space, or spacing interval, results in the strip being fed forward. The second way is dependent upon the reception of a specific signal. To enable word spaces to be inserted in these two ways, two additional exploring blades I53 and I54 (Figure 11) are mounted on the spindle I8. These exploring blades I53 and I54 are such that either one may be rendered capable of operation but not both simultaneously. Thus, a manually operable lever 250, arranged to assume two positions corresponding to the two ways in which word spaces may be introduced, is mounted so that 11 it is moved to one position its upper end lies under the exploring blade I53, with the result that this blade can in no circumstances enter notches in the combs 56, 25I and I4, while the blade I 54 is free to enter its associated notches if these are brought into register. On the other hand, if the lever 250 is moved to its other position its upper end lies under the exploring blade I54 so that this blade can in no circumstances enter notches in the combs 56, 25I and I4, while the blade I53 is capable of entering its associated notches if these are in register. The exploring blade I53 is associated with notches in the permutation combs 56 and the additional comb 25I that are in register when these combs are in their normal positions, that is to say the positions in which they lie when they are not actuated by the L-shaped levers 31a 37!, 38a 38f and.38:r. However, as in the case of the other exploring blades, the exploring blade I53 can only enter its associated slots when the space comb I4 is acted upon by the cross bar la of the actuator I, acting through the intermediate member I8. The exploring blade I 53 therefore enters its corresponding slots in the combs, provided the lever 250 is appropriately set, upon every spacing interval other than a spacing interval immediately following a signal, because during every such spacing interval no permutation comb 56 or comb 25I is moved and the actuator I traverses a path such that the space comb I4 is actuated. Thus, supposing the last character in a word is to be followed by a word space and the lever 250 is in the position in which it leaves the blade I53 free but holds up the blade I54, three spacing intervals are provided between the last impulse of the permutation representing the character and the first impulse of the permutation representing the first character of the next word. The first of these spacing intervals is the one that follows every permutation and the corresponding movementof the space comb I4 enables the selected exploring blade I2 to enter its corresponding notches in the combs. When this happens the exploring blade I53 cannot enter notches in the combs because one or more of the permutation combs has been moved due to the setting up of the permutation representing the last character in the word so that the notches corresponding to the blade I53 are not all in register. However, the permutation comb or combs that have been moved are then immediately unlatched by their latch members 13 so that during the next two spacing intervals all the permutation combs are in their initial positions. Thus, during the next two spacing intervals the corresponding two movements of the space comb 14 permit the exploring blade I53 to enter its notches. This actuation of the exploring blade I53 causes mechanism described below to cause the strip feed ratchet wheel I 48 to he stepped round twice. Actually the paper is stepped forward three times between the two words because, in addition to the two movements due to the exploring blade I53 there is the usual letter space movement that takes place automatically (as already described) due to the actuation of the lever 32 and its associated mechanism (shown in Figure 9) immediately before the printing of the first character in the next word.

Now, assuming that the exploring blade I54 is freed by the lever 250 while this lever puts the exploring blade I53 out of action, then thecondition of the apparatus is such that the word space has to be inserted by the transmission of a special signal consisting of a permutation that results in the permutation combs 56 being set so as to bring the notches corresponding to the exploring blade I54 into register. Thus, when the permutation corresponding to the last character in a word has been transmitted, the permutation which results in the actuation of the exploring blade I5 is transmitted. This, as mentioned above, results in the permutation being set up on the permutation combs 56, and the space comb 14 is thereupon moved because the effect of the signal on the apparatus so far as the combs and their actuating mechanism are concerned, is the same as that of any ordinary character signal. Thus, the paper. strip is fed forward by an amount equal to the ordinary letter space through the medium of the lever I32 and its associated mechanism shown in Figure 9. The paper strip is then immediately stepped forward once more by an amount equal to an ordinary letter space, as a result of the entry of the exploring blade I55 into its associated notches in the combs. The mechanism through the medium of which the exploring blade I54 causes the paper strip to be fed forward is that described below, which is associated for the same purpose with the exploring blade I53. If a character signal representing the first character in a new word immediately follows the word space signal, the paper strip is stepped forward once more before this character is printed on. account of the movement of the lever I32 and its associated mechanism that takes place when the space comb 14 is shifted to permit the exploring bled 12 corresponding to the character to enterslots in the combs. Thus, the paper strip is stepped forward three times if a word space signal is introduced once between two words. In'the above description it has been assumed that the word spaces are introduced between two words but, of course, the spaces may be introduced between any two printed characters whether these are letters, numerals, plmctuation marks or other signs. Further, the space between two characters may be made longer than the space provided when the strip is fed forward three consecutive times. Thus, when the exploring blade I53 is capable of operation, any desired number of spacing intervals may be introduced between the last perforation in the perforations representing one character and the first perforation in the perforations representing the next character.

Also, when the exploring blade I54 is in operation,

any number of consecutive spacing signals may be sent.

When either one of the exploring blades l53 and I54 is in operation and when its associated notches are not in register, the engagement of the exploring blade with the upper surface of the combs causes the exploring blade to follow a path such that a lug I531: or I54a does not engage 9. lug I55a on a frame I55 pivoted about the axis of a horizontal spindle I05. When, however, the blade enters its associated notches, its lug I530 or I 54a engages the lug I55a and causes the frame I55 to swing about the axis of the spindle I05 against the action of a spring I58 connected between an arm I56aon a pivoted member I56 and an arm I 5517 of the frame I55. The movement of the frame I55 and the consequent straining of the spring I58 results in a lug I560 on the member I56 moving out of a notch I550 in the arm I55b of the frame I55. As soon as the lug I560 leaves the notch I550, the spring I58 urges the lug I560 to one side of the notch I550 so that as soon as the exploring blade that has moved the frame I55'moves out of engagement with the lug I55a, the frame I55 does not return to its initial position but is latched in the position to which it has been moved on account of the engagement between the lug I560 and the edge of the arm I55b of the frame I55. When the frame I55 is turned to the latter position, a member I51 is no longer prevented by it from being lowered to a position such that a wide part I51d of the member I51 is interposed between the bent-over upper end I6Iia of a dog I60 and an arm I361: of the member I36. The dog I60 is fixed to link II which is continuously reciprocated by the eccentric Ill and which causes the frame 8, carrying the actuator I, to be rocked up and down. Before the member I51 is lowered, the dog I60 is reciprocated beneath the level of a shoulder I510 on the member I51 and does not move this member. When,

however, the frame I55 is lowered, the bent-over part IBM is immediately beneath the shoulder I510 but is soon afterwards moved to beyond the shoulder I510 so that the member I51 can follow the frame I55 downwards. The dog I60 then engages the edge of the wide part I51d of the member I51 and pushes on it so that the member I51 is swung about the axis of the spindle I and pushes on an arm I36b of the member I36 with the result that this member I36 is turned. This movement of the member I36 causes the rod I31 to be pulled and the stop member I38 (Figure 10) to be removed from the path of the lug 5a on the pawl I65 so that the ratchet wheel I 48 is stepped round and the paper strip is stepped forward. Further, this movement of the member I36 causes its arm I360 to act on the end I56b of is then free to return the stop member I38, the rod I31 and the member I36 to their initial positions.

The spindle I passes through a slot I51a formed in the member I51 (see Figure 9) while the latter is connected by a spring I59 (see Figure 11) to the arm I55b of the frame I55. This arrangement permits the member I51 to fall and rise in the manner described above.

It may be mentioned that the two-position lever 250 may be arranged to be moved automatically instead of manually.

When there is a large interval between two sets of signals, that is to say, when signal traffic is interrupted for a considerable time, and when the exploring blade I53 is operative, it is often desirable to prevent the paper strip being fed forward continuously between the time when trafllc ceases and the time when traflic starts again. Accordingly, the paper strip feed may be stopped by depressing a button I6I (Figure 9) on a slip saver lever I62 pivoted about the axis of a spindle I63, the slip saver lever I62 being moved against the action of a spring I62a. The depression of the slip saver lever I62 causes a lug I62b to depress one end of the interposed member 16 so that the latter is tilted, against the action of a spring (not shown), about the axis of the spindle I33. When the slip saver lever I62 is depressed, it is latched in the depressed position because the end of a leaf spring I64, fixed to a downwardly extending part I62c of the slip saver" lever I62, engages behind a shoulder formed on a fixed member I65. Thus the interposed member 16 is held in its tilted position until the slip saver" lever I62 is unlatched. When the interposed member 16 is in its tilted position, the transverse bar 1a of the actuator 1 cannot act on it so as to shift the space comb 14. Accordingly the exploring blade I53 is prevented from entering notches in the combs as long as the interposed member is tilted. Consequently, the paper strip is not moved forward on account of the actuation of the exploring blade I53.

I! trafllc begins when the interposed member 16 is tilted, the result is that the interposed member 16 is returned automatically and immediately to its operative position. The reason for this is that the first impulse inthe first signal causes, in the manner described above, one or other of the L-shaped levers 31a or 38a to turn the lever I30 so as to swing the lever I32 downwards. Thus, a downwardly extending arm I66 formed on the lever I32 pushes laterally on the blade spring I64 and moves it out of engagement with the shoulder on the fixed member I65. The spring I62a is, therefore, permitted to raise the slip saver lever I62 so as to allow the interposed member 16 to be returned to its operative position. The return movement of the interposed member 16 is limited by a stop 16a. The interposed member 16 is returned to its operative position in time to enable the actuator I to actuate the space comb 14 during the spacing interval immediately following the first signal, so that the character corresponding to the signal is printed. The lever I32 is actuated so that the paper strip is stepped forward once prior to the printing of this signal.

Frequently it is desirable for mechanism to be provided which enables the operator of a transmitter to actuate some call device in a receiver or to perform an analogous function. In the illustrated apparatus such mechanism is provided. The mechanism includes an exploring blade I10 (Figure 12) which is actuated in the same way as the other exploring blades and is associated with a three-armed lever I04 which is the same as the three-armed levers I 04 associated with the exploring blades 12. When it is desired to operate the call device a special signal is transmitted which results in the permutation combs 16 being set so that the exploring blade I10 can enter registering notches in these, with the result that a lug I 10a depresses the arm I 0411 of the threearmed lever I04 associated with the exploring blade I10.

The arm I04a of the three-armed lever I04 bears on a bell-crank lever HI and swings it about the axis of a horizontal spindle I12 in such a direction that it bears'on a bell-crank lever I 11 and swings the latter about the axis of a spindle I13a. This movement of the bell-crank lever I11 results in its end I11a pressing together two pairs of contact springs I18 and thereby closing contacts so as to start a perforator or set some other instrument into operation. The two springs I18 lying in the vertical plane adjacent the end I11a of the bell-crank lever I11 are connected together by an insulating block I18a. The bell-crank lever I11 is connected to a bell-crank lever I15 by a spring I16 which, when'the contacts are closed, is stretched and causes the shoulder of a lug I15a of the bell-crank lever I15 to engage the edge of a vertical lug I11b on the bell-crank lever I11. Thus, the lever I11 is latched in the position to which it is moved and the contacts are maintained closed after the exploring blade I10 has been raised from its operative engagement with the combs (so as to permit the spring I13 to return the bell crank lever toward the position shown in Figure 12 and thereafter for a indefinite period). The actuation of the instrument controlled by the contacts on the contact springs I18 may be stopped at will by the operator of the transmitter by sending a further special signal. This signal results in the permutation combs 56 being set so that a further exploring blade 252 can enter registering notches in them. When this happens a lug 252a bears on the arm I04a of an associated three-armed lever I04 which in turn bears on a bell crank lever I19 and swings it in a clockwise direction, as seen in Figure 12, about the axis of a spindle I80. Thus, a rod I8I, connected between the bell crank lever I18 and a bell crank lever I14, is pulled so as to swing the bell crank lever I14 against the action of a tension spring I13. The arm I14a of the bell crank lever I14 then swings the bell crank lever I15, against the action of the spring I16, about a vertical axis H51) in a clockwise direction, as seen in Figure 12, so that the lug N51: is removed from engagement with the edge of the lug I11b and the end "111 of the bell crank lever I11 is withdrawn from engagement with the contact springs I18 which separate due to their inherent springiness. The controlled circuit is, therefore, opened and the parts are returned to their initial position, shown in Figure 6 12, with the edge of the lug I15a bearing against the face 01 the lug "1:1.

The three-armed levers I 04 associated with the exploring blades I10 and 252 are not associated directly with any printing mechanism but are provided for association with scrutinizer mechanism described below.

The apparatus is provided with mechanism arranged to print a distinctive mark on the paper strip and to send a distinctive signal to the operator of the transmitter in the event of a fault resulting in a mis-selection leading to none 01 the exploring blades I2, I53, I 54, I10, 252 being able to enter registering notches in the permutation combs or to two signals being run together without an intervening spacing interval. Thus, in addition to the other exploring blades, the spindle I9 carries a scrutinizer blade I82 (Figure 13). This is associated with a threearmed lever I83 that is somewhat different from the three-armed levers I04 associated with the other exploring blades. The scrutinizer blade I82 is associated with wide slots in all the combs except the space comb I4 so that it would enter these slots at each centre-hole interval, upon being brought to bear on the combs, were it not for the space comb 14. Thus, as soon as the space comb I4 is actuated, slots are arranged for the reception of the scrutinizer blade I82, whatever the setting of the permutation combs 56 and additional comb 25I. When, therefore, the permutation combs 58 and space comb I4 have been set according to an incoming signal, the movement of the spindle I9 and the setting of the combs is such that the blade I82 tends to be moved downwards and upwards with its upwardly extending part I82a held continuously against the rest 99 by the spring I82b. However, if, during the downward movement one of the other exploring blades I2, I53, I54, I10, 252 enters its corresponding notches in the combs, the associated three-armed lever I04 or frame I55 is rocked about the axis of the spindle I05 as described above. During this movement its arm I04b (the frame I55, like the three-armed levers I04, is provided with an arm I 0417) bears on a cross-member I88, extending above all the threearmed levers I04 and the frame I55 and fixed to an arm I86 pivoted about the axis of the spindle I05, and thereby causes the arm I88 to be swung against the action of a spring I8'I, in an anti-clockwise direction as seen in Figure 13.

The upper end of the arm I86 then acts on a cam surface I90a. on one arm of a bell crank lever I90 and causes this to be swung about-the axis of a spindle WI. The lower end of the bell crank lever I90 is thus caused to thrust the upwardly extending part I820. of the scrutinizer blade I82 away from the rest 99. A lateral lug I82c at the upper end of the part IBM is accordingly caused to traverse a path such that it does not engage a lug at the end of an arm I 83a on the three-armed lever I83 but passes down to the right of this lug, as seen-in Figure 13. On the other hand, if the bell crank lever I90 is not actuated because of a mis-selection resulting in none of the three-armed levers I04 nor the frame 55 being actuated, the arm I82a is held against the bar 99 during the whole time that the scrutinizer blade I82 is within its notches and the lug I82c traverses a path such that it engages the lug on the arm I830. of the three-armed lever I83 and turns this so that it is latched by a hook member I84 exactly similar to the hook members I06. The three-armed lever I83 is associated with type-actuating mechanism in exactly the same way as the three-armed levers I04 so that a warning mark is printed on the paper strip when the scrutinizer blade I82 ,is rendered op erative.

The additional comb 25I is for co-operation with the scrutinizer blade I82. As the apparatus is designed to operate in conjunction with code in which no signal is composed of more than six impulses, the scrutinizer comb 25I is never shifted to the left, as seen in Figure 3, during normal operation of the apparatus. This, of course, is

because a spacing interval always intervenes before the actuator I has an opportunity of actuating the interposed member I9g (Figure 3). When, however, a fault results in the omission of one or more of thespacing intervals that should exist between consecutive signals so that the two or more signals are run together, the result is usually that seven or more immediately adjacent impulses are received. Consequently, all seven interposed members I9a I9g are unlatched in succession and acted upon by the actuator I. When the actuator I acts on the interposed member I9g and causes the'corresponding rocking plate 229 to swing about the axis of the spindle 23 so as to raise the L-shaped lever 3811:, the latter is swung about its axis due to its engagement either with the cross piece 41 on the armature frame M or with the cross piece 48 on the armature 42. As previously explained, the L- shaped lever 38:1: is turned, upon being raised,

whether the impulse which causes it to be raised is a dash impulse or adot impulse because in the one case the cross piece 48 engages the part 54 of the L-shaped lever 38:1,, while in the other case the cross piece 41 engages the part of the L-shaped lever on the side of its notch, remote from the part 54. When the L-shaped lever 38a: is turned, it pushes the scrutinizer comb 25I to the left and the comb 25I is latched in the operative position to which it is moved by its associated latching member I3. The comb 25I is formed with notches which, when the comb is in its zero-or initial position, are in positions such as to enable any of the exploring blades to enter registering notches in the permutation combs 56 and space comb I4. When, however, the scru-. tinizer comb 25I is in its operative position the high parts of the comb between its notches register with all the exploring blades except the scrutinizer blade. The result of this is that when the space comb I4 is shifted none of the exploring blades I2, I53, I54, I10 and 252 can enter registering notches. They are all, therefore, prevented from acting on their associated three-armed levers to swing the arm I85, while the part I82a of the scrutinizer blade I82 follows the path in which it rests continuously against the rest 99 and causes the warning mark to be printed.

A further exploring blade (not shown) is provided which is arranged to enter alined notches whenever the combs 56 and 25I are in their initial or zero positions and only the space comb has been moved. This further exploring blade is not associated with any printing or other mechanism but is only associated with an extra three-armed lever I04. This further exploring blade ensures the scrutirnzer mechanism functioning properly when the word space exploring blade I54 is in operation. Thus, when no signal is being sent, i. e., when no character, word space or other signal is being received and the apparatus is in operation so that the exploring blades are continuously being brought into engagement with the combs, the further exploring blade enters alined notches in the combs and swings its associated three-armed lever I04 so as to act on the bar I88 and turn the arm I 88, thereby preventing the scrutinizer blade I82 from causing successive warning marine from being printed.

It will be appreciated that this is necessary because when no signals are receivedand the exploring blade I53 is out of action, none of the three-armed levers I04 and frame I55 associated with the exploring blades I2, I53, I54, I10 and 

